Tips for creating an animated music video?
Import your song into a music program such as LMMS, and map out the beat with a drum instrument, using kick for the main beat, crashes for points where the track shifts into a high or low, and snares or a different-sounding drum for various points where you want characters to do certain things without the track shifting into a high or low.


Once you export the mapped audio track (just the drums; delete the main song), import it into Blender making sure that the first frames of the main song and the mapped audio track are aligned perfectly. Mute the song and work on your anim relying on the mapped drum pattern.


While mapping out your song, have a word document open. Write the time and what action takes place. Example:
2:43 (James draws sword) (the two characters are in standoff) 
2:47 (James races forward to attack)


You can timestamp as much as you want, on many actions as you want. Just be sure to mark your track with the appropriate snare or crash if there are certain character actions that need to be signified. 


If there are lyrics, go into Blender and animate them, replacing the current line of text every time there's a new sentence or stanza. Animating them syllable by syllable helps.


That's it so far! I'm working on my own music video in Blender too and I found all this stuff out the hard way. Perhaps once I finish and release the actual product, I'll release a BTS video sharing everything I learned and discovered. 

Good luck on your music video!

EDIT: Obviously, you need to determine the frames per beat in order to sync to the music. Here's what you can do. Determine the BPM of you song here: https://getsongbpm.com/tools/audio

Then calculate the frames per beat of your song here: https://www.vjamm.com/support_av_bpm.php%3Flang=en.html

Adjust the value of your framerate until the frames per beat is at a whole number. Then, type in that framerate value into Blender (make sure to set it at custom), adjusting the base value underneath until the numbers on the framerate are correct. 
For my project, I had a framerate of 24.4.